The invention relates to a combustion chamber pressure gauge for measuring the pressure in a combustion chamber of an internal combustion engine. Pressure gauges of this type are generally known from DE 10 2010 037 476 A1. In such combustion chamber pressure gauges, a plunger is displaced against a restoring force under the effect of combustion chamber pressure. The axial displacement of the plunger, as the measure of the combustion chamber pressure, is detected by means of a sensor.